[SPARK-16779][TRIVIAL] Avoid using postfix operators where they do not add much and remove whitelisting

## What changes were proposed in this pull request?

Avoid using postfix operation for command execution in SQLQuerySuite where it wasn't whitelisted and audit existing whitelistings removing postfix operators from most places. Some notable places where postfix operation remains is in the XML parsing & time units (seconds, millis, etc.) where it arguably can improve readability.

## How was this patch tested?

Existing tests.

Author: Holden Karau <holden@us.ibm.com>

Closes #14407 from holdenk/SPARK-16779.

21 files changed, 6 insertions, 33 deletions

diff --git a/core/src/main/scala/org/apache/spark/deploy/SparkHadoopUtil.scala b/core/src/main/scala/org/apache/spark/deploy/SparkHadoopUtil.scala
index 90c71cc6cf..671e8e4484 100644
--- a/core/src/main/scala/org/apache/spark/deploy/SparkHadoopUtil.scala
+++ b/core/src/main/scala/org/apache/spark/deploy/SparkHadoopUtil.scala
@@ -25,7 +25,6 @@ import java.util.{Arrays, Comparator, Date}
 
 import scala.collection.JavaConverters._
 import scala.concurrent.duration._
-import scala.language.postfixOps
 import scala.util.control.NonFatal
 
 import com.google.common.primitives.Longs
diff --git a/core/src/main/scala/org/apache/spark/scheduler/TaskSchedulerImpl.scala b/core/src/main/scala/org/apache/spark/scheduler/TaskSchedulerImpl.scala
index 2ce49ca134..dc05e764c3 100644
--- a/core/src/main/scala/org/apache/spark/scheduler/TaskSchedulerImpl.scala
+++ b/core/src/main/scala/org/apache/spark/scheduler/TaskSchedulerImpl.scala
@@ -25,7 +25,6 @@ import java.util.concurrent.atomic.AtomicLong
 import scala.collection.mutable.ArrayBuffer
 import scala.collection.mutable.HashMap
 import scala.collection.mutable.HashSet
-import scala.language.postfixOps
 import scala.util.Random
 
 import org.apache.spark._
diff --git a/core/src/main/scala/org/apache/spark/util/RpcUtils.scala b/core/src/main/scala/org/apache/spark/util/RpcUtils.scala
index 2bb8de568e..e3b588374c 100644
--- a/core/src/main/scala/org/apache/spark/util/RpcUtils.scala
+++ b/core/src/main/scala/org/apache/spark/util/RpcUtils.scala
@@ -17,8 +17,6 @@
 
 package org.apache.spark.util
 
-import scala.language.postfixOps
-
 import org.apache.spark.SparkConf
 import org.apache.spark.rpc.{RpcAddress, RpcEndpointRef, RpcEnv, RpcTimeout}
 
diff --git a/core/src/test/scala/org/apache/spark/HeartbeatReceiverSuite.scala b/core/src/test/scala/org/apache/spark/HeartbeatReceiverSuite.scala
index 5e2ba311ee..5f59c176ab 100644
--- a/core/src/test/scala/org/apache/spark/HeartbeatReceiverSuite.scala
+++ b/core/src/test/scala/org/apache/spark/HeartbeatReceiverSuite.scala
@@ -22,7 +22,6 @@ import java.util.concurrent.{ExecutorService, TimeUnit}
 import scala.collection.Map
 import scala.collection.mutable
 import scala.concurrent.duration._
-import scala.language.postfixOps
 
 import org.mockito.Matchers
 import org.mockito.Matchers._
diff --git a/core/src/test/scala/org/apache/spark/deploy/history/ApplicationCacheSuite.scala b/core/src/test/scala/org/apache/spark/deploy/history/ApplicationCacheSuite.scala
index 4ab000b53a..e3304be792 100644
--- a/core/src/test/scala/org/apache/spark/deploy/history/ApplicationCacheSuite.scala
+++ b/core/src/test/scala/org/apache/spark/deploy/history/ApplicationCacheSuite.scala
@@ -23,7 +23,6 @@ import javax.servlet.http.{HttpServletRequest, HttpServletResponse}
 
 import scala.collection.mutable
 import scala.collection.mutable.ListBuffer
-import scala.language.postfixOps
 
 import com.codahale.metrics.Counter
 import com.google.common.cache.LoadingCache
diff --git a/core/src/test/scala/org/apache/spark/rdd/PipedRDDSuite.scala b/core/src/test/scala/org/apache/spark/rdd/PipedRDDSuite.scala
index 59b90974ae..387f3e2502 100644
--- a/core/src/test/scala/org/apache/spark/rdd/PipedRDDSuite.scala
+++ b/core/src/test/scala/org/apache/spark/rdd/PipedRDDSuite.scala
@@ -21,7 +21,6 @@ import java.io.File
 
 import scala.collection.Map
 import scala.io.Codec
-import scala.language.postfixOps
 import scala.sys.process._
 import scala.util.Try
 
@@ -215,7 +214,8 @@ class PipedRDDSuite extends SparkFunSuite with SharedSparkContext {
   }
 
   def testCommandAvailable(command: String): Boolean = {
-    Try(Process(command) !!).isSuccess
+    val attempt = Try(Process(command).run().exitValue())
+    attempt.isSuccess && attempt.get == 0
   }
 
   def testExportInputFile(varName: String) {
diff --git a/core/src/test/scala/org/apache/spark/storage/MemoryStoreSuite.scala b/core/src/test/scala/org/apache/spark/storage/MemoryStoreSuite.scala
index 145d432afe..c11de82667 100644
--- a/core/src/test/scala/org/apache/spark/storage/MemoryStoreSuite.scala
+++ b/core/src/test/scala/org/apache/spark/storage/MemoryStoreSuite.scala
@@ -20,7 +20,6 @@ package org.apache.spark.storage
 import java.nio.ByteBuffer
 
 import scala.language.implicitConversions
-import scala.language.postfixOps
 import scala.language.reflectiveCalls
 import scala.reflect.ClassTag
 
diff --git a/external/kafka-0-10/src/main/scala/org/apache/spark/streaming/kafka010/KafkaTestUtils.scala b/external/kafka-0-10/src/main/scala/org/apache/spark/streaming/kafka010/KafkaTestUtils.scala
index ecabe1c365..e73823e898 100644
--- a/external/kafka-0-10/src/main/scala/org/apache/spark/streaming/kafka010/KafkaTestUtils.scala
+++ b/external/kafka-0-10/src/main/scala/org/apache/spark/streaming/kafka010/KafkaTestUtils.scala
@@ -25,7 +25,6 @@ import java.util.concurrent.TimeoutException
 
 import scala.annotation.tailrec
 import scala.collection.JavaConverters._
-import scala.language.postfixOps
 import scala.util.control.NonFatal
 
 import kafka.admin.AdminUtils
@@ -279,4 +278,3 @@ private[kafka010] class KafkaTestUtils extends Logging {
     }
   }
 }
-
diff --git a/external/kafka-0-8/src/main/scala/org/apache/spark/streaming/kafka/KafkaTestUtils.scala b/external/kafka-0-8/src/main/scala/org/apache/spark/streaming/kafka/KafkaTestUtils.scala
index abfd7aad4c..03c9ca7524 100644
--- a/external/kafka-0-8/src/main/scala/org/apache/spark/streaming/kafka/KafkaTestUtils.scala
+++ b/external/kafka-0-8/src/main/scala/org/apache/spark/streaming/kafka/KafkaTestUtils.scala
@@ -25,7 +25,6 @@ import java.util.concurrent.TimeoutException
 
 import scala.annotation.tailrec
 import scala.collection.JavaConverters._
-import scala.language.postfixOps
 import scala.util.control.NonFatal
 
 import kafka.admin.AdminUtils
@@ -274,4 +273,3 @@ private[kafka] class KafkaTestUtils extends Logging {
     }
   }
 }
-
diff --git a/graphx/src/main/scala/org/apache/spark/graphx/lib/PageRank.scala b/graphx/src/main/scala/org/apache/spark/graphx/lib/PageRank.scala
index 0a1622bca0..2f5bd4ed4f 100644
--- a/graphx/src/main/scala/org/apache/spark/graphx/lib/PageRank.scala
+++ b/graphx/src/main/scala/org/apache/spark/graphx/lib/PageRank.scala
@@ -17,7 +17,6 @@
 
 package org.apache.spark.graphx.lib
 
-import scala.language.postfixOps
 import scala.reflect.ClassTag
 
 import org.apache.spark.graphx._
@@ -109,7 +108,7 @@ object PageRank extends Logging {
     require(resetProb >= 0 && resetProb <= 1, s"Random reset probability must belong" +
       s" to [0, 1], but got ${resetProb}")
 
-    val personalized = srcId isDefined
+    val personalized = srcId.isDefined
     val src: VertexId = srcId.getOrElse(-1L)
 
     // Initialize the PageRank graph with each edge attribute having
diff --git a/mllib/src/main/scala/org/apache/spark/mllib/util/MFDataGenerator.scala b/mllib/src/main/scala/org/apache/spark/mllib/util/MFDataGenerator.scala
index 898a09e516..42c5bcdd39 100644
--- a/mllib/src/main/scala/org/apache/spark/mllib/util/MFDataGenerator.scala
+++ b/mllib/src/main/scala/org/apache/spark/mllib/util/MFDataGenerator.scala
@@ -19,7 +19,6 @@ package org.apache.spark.mllib.util
 
 import java.{util => ju}
 
-import scala.language.postfixOps
 import scala.util.Random
 
 import org.apache.spark.SparkContext
diff --git a/repl/src/test/scala/org/apache/spark/repl/ExecutorClassLoaderSuite.scala b/repl/src/test/scala/org/apache/spark/repl/ExecutorClassLoaderSuite.scala
index 12e98565dc..3d622d42f4 100644
--- a/repl/src/test/scala/org/apache/spark/repl/ExecutorClassLoaderSuite.scala
+++ b/repl/src/test/scala/org/apache/spark/repl/ExecutorClassLoaderSuite.scala
@@ -27,7 +27,6 @@ import java.util
 import scala.concurrent.duration._
 import scala.io.Source
 import scala.language.implicitConversions
-import scala.language.postfixOps
 
 import com.google.common.io.Files
 import org.mockito.Matchers.anyString
diff --git a/sql/catalyst/src/test/scala/org/apache/spark/sql/types/DecimalSuite.scala b/sql/catalyst/src/test/scala/org/apache/spark/sql/types/DecimalSuite.scala
index e1675c9590..a10c0e39eb 100644
--- a/sql/catalyst/src/test/scala/org/apache/spark/sql/types/DecimalSuite.scala
+++ b/sql/catalyst/src/test/scala/org/apache/spark/sql/types/DecimalSuite.scala
@@ -17,8 +17,6 @@
 
 package org.apache.spark.sql.types
 
-import scala.language.postfixOps
-
 import org.scalatest.PrivateMethodTester
 
 import org.apache.spark.SparkFunSuite
diff --git a/sql/core/src/test/scala/org/apache/spark/sql/DataFrameSuite.scala b/sql/core/src/test/scala/org/apache/spark/sql/DataFrameSuite.scala
index 62cfd24041..499f318037 100644
--- a/sql/core/src/test/scala/org/apache/spark/sql/DataFrameSuite.scala
+++ b/sql/core/src/test/scala/org/apache/spark/sql/DataFrameSuite.scala
@@ -21,7 +21,6 @@ import java.io.File
 import java.nio.charset.StandardCharsets
 import java.util.UUID
 
-import scala.language.postfixOps
 import scala.util.Random
 
 import org.scalatest.Matchers._
diff --git a/sql/core/src/test/scala/org/apache/spark/sql/DatasetAggregatorSuite.scala b/sql/core/src/test/scala/org/apache/spark/sql/DatasetAggregatorSuite.scala
index ddc4dcd239..b117fbd0bc 100644
--- a/sql/core/src/test/scala/org/apache/spark/sql/DatasetAggregatorSuite.scala
+++ b/sql/core/src/test/scala/org/apache/spark/sql/DatasetAggregatorSuite.scala
@@ -17,8 +17,6 @@
 
 package org.apache.spark.sql
 
-import scala.language.postfixOps
-
 import org.apache.spark.sql.catalyst.encoders.ExpressionEncoder
 import org.apache.spark.sql.expressions.Aggregator
 import org.apache.spark.sql.expressions.scalalang.typed
diff --git a/sql/core/src/test/scala/org/apache/spark/sql/DatasetCacheSuite.scala b/sql/core/src/test/scala/org/apache/spark/sql/DatasetCacheSuite.scala
index ac9f6c2f38..8d5e9645df 100644
--- a/sql/core/src/test/scala/org/apache/spark/sql/DatasetCacheSuite.scala
+++ b/sql/core/src/test/scala/org/apache/spark/sql/DatasetCacheSuite.scala
@@ -17,8 +17,6 @@
 
 package org.apache.spark.sql
 
-import scala.language.postfixOps
-
 import org.apache.spark.sql.functions._
 import org.apache.spark.sql.test.SharedSQLContext
 
diff --git a/sql/core/src/test/scala/org/apache/spark/sql/DatasetPrimitiveSuite.scala b/sql/core/src/test/scala/org/apache/spark/sql/DatasetPrimitiveSuite.scala
index 6aa3d3fe80..f8d4c61967 100644
--- a/sql/core/src/test/scala/org/apache/spark/sql/DatasetPrimitiveSuite.scala
+++ b/sql/core/src/test/scala/org/apache/spark/sql/DatasetPrimitiveSuite.scala
@@ -17,8 +17,6 @@
 
 package org.apache.spark.sql
 
-import scala.language.postfixOps
-
 import org.apache.spark.sql.test.SharedSQLContext
 
 case class IntClass(value: Int)
diff --git a/sql/core/src/test/scala/org/apache/spark/sql/DatasetSuite.scala b/sql/core/src/test/scala/org/apache/spark/sql/DatasetSuite.scala
index 8a756fd474..88fb1472b6 100644
--- a/sql/core/src/test/scala/org/apache/spark/sql/DatasetSuite.scala
+++ b/sql/core/src/test/scala/org/apache/spark/sql/DatasetSuite.scala
@@ -20,8 +20,6 @@ package org.apache.spark.sql
 import java.io.{Externalizable, ObjectInput, ObjectOutput}
 import java.sql.{Date, Timestamp}
 
-import scala.language.postfixOps
-
 import org.apache.spark.sql.catalyst.encoders.{OuterScopes, RowEncoder}
 import org.apache.spark.sql.catalyst.util.sideBySide
 import org.apache.spark.sql.execution.streaming.MemoryStream
diff --git a/sql/hive/src/test/scala/org/apache/spark/sql/hive/execution/SQLQuerySuite.scala b/sql/hive/src/test/scala/org/apache/spark/sql/hive/execution/SQLQuerySuite.scala
index b659325a62..e6fe47aa65 100644
--- a/sql/hive/src/test/scala/org/apache/spark/sql/hive/execution/SQLQuerySuite.scala
+++ b/sql/hive/src/test/scala/org/apache/spark/sql/hive/execution/SQLQuerySuite.scala
@@ -1790,6 +1790,7 @@ class SQLQuerySuite extends QueryTest with SQLTestUtils with TestHiveSingleton {
   }
 
   def testCommandAvailable(command: String): Boolean = {
-    Try(Process(command) !!).isSuccess
+    val attempt = Try(Process(command).run().exitValue())
+    attempt.isSuccess && attempt.get == 0
   }
 }
diff --git a/streaming/src/test/scala/org/apache/spark/streaming/InputStreamsSuite.scala b/streaming/src/test/scala/org/apache/spark/streaming/InputStreamsSuite.scala
index 00d506c2f1..9ecfa48091 100644
--- a/streaming/src/test/scala/org/apache/spark/streaming/InputStreamsSuite.scala
+++ b/streaming/src/test/scala/org/apache/spark/streaming/InputStreamsSuite.scala
@@ -25,7 +25,6 @@ import java.util.concurrent.atomic.AtomicInteger
 
 import scala.collection.JavaConverters._
 import scala.collection.mutable
-import scala.language.postfixOps
 
 import com.google.common.io.Files
 import org.apache.hadoop.fs.Path
diff --git a/yarn/src/main/scala/org/apache/spark/deploy/yarn/AMDelegationTokenRenewer.scala b/yarn/src/main/scala/org/apache/spark/deploy/yarn/AMDelegationTokenRenewer.scala
index a6a4fec3ba..310a7a6b05 100644
--- a/yarn/src/main/scala/org/apache/spark/deploy/yarn/AMDelegationTokenRenewer.scala
+++ b/yarn/src/main/scala/org/apache/spark/deploy/yarn/AMDelegationTokenRenewer.scala
@@ -19,8 +19,6 @@ package org.apache.spark.deploy.yarn
 import java.security.PrivilegedExceptionAction
 import java.util.concurrent.{Executors, TimeUnit}
 
-import scala.language.postfixOps
-
 import org.apache.hadoop.conf.Configuration
 import org.apache.hadoop.fs.{FileSystem, Path}
 import org.apache.hadoop.security.UserGroupInformation
@@ -128,7 +126,7 @@ private[yarn] class AMDelegationTokenRenewer(
     try {
       val remoteFs = FileSystem.get(freshHadoopConf)
       val credentialsPath = new Path(credentialsFile)
-      val thresholdTime = System.currentTimeMillis() - (daysToKeepFiles days).toMillis
+      val thresholdTime = System.currentTimeMillis() - (daysToKeepFiles.days).toMillis
       hadoopUtil.listFilesSorted(
         remoteFs, credentialsPath.getParent,
         credentialsPath.getName, SparkHadoopUtil.SPARK_YARN_CREDS_TEMP_EXTENSION)